18FTHK5351 PET Imaging in Patients with Mild Cognitive Impairment

Background@#and PurposeMild cognitive impairment (MCI) is a condition with diverse clinical outcomes and subgroups. Here we investigated the topographic distribution of tau in vivo using the positron emission tomography (PET) tracer [18F]THK5351 in MCI subgroups. @*Methods@#This study included 96 participants comprising 38 with amnestic MCI (aMCI), 21 with nonamnestic MCI (naMCI), and 37 with normal cognition (NC) who underwent 3.0-T MRI, [18F]THK5351 PET, and detailed neuropsychological tests. [18F]flutemetamol PET was also performed in 62 participants. The aMCI patients were further divided into three groups: 1) verbal-aMCI, only verbal memory impairment; 2) visual-aMCI, only visual memory impairment; and 3) both-aMCI, both visual and verbal memory impairment. Voxel-wise statistical analysis and region-of-interest -based analyses were performed to evaluate the retention of [18F]THK5351 in the MCI subgroups. Subgroup analysis of amyloid-positive and -negative MCI patients was also performed. Correlations between [18F]THK5351 retention and different neuropsychological tests were evaluated using statistical parametric mapping analyses. @*Results@#[18F]THK5351 retention in the lateral temporal, mesial temporal, parietal, frontal, posterior cingulate cortices and precuneus was significantly greater in aMCI patients than in NC subjects, whereas it did not differ significantly between naMCI and NC participants. [18F] THK5351 retention was greater in the both-aMCI group than in the verbal-aMCI and visualaMCI groups, and greater in amyloid-positive than amyloid-negative MCI patients. The cognitive function scores were significantly correlated with cortical [18F]THK5351 retention. @*Conclusions@#[18F]THK5351 PET might be useful for identifying distinct topographic patterns of [18F]THK5351 retention in subgroups of MCI patients who are at greater risk of the progression to Alzheimer's dementia.

Relationships between ¹⁸F-THK5351 Retention and Language Functions in Primary Progressive Aphasia

BACKGROUND AND PURPOSE: There are three distinct subtypes of primary progressive aphasia (PPA): the nonfluent/agrammatic variant (nfvPPA), the semantic variant (svPPA), and the logopenic variant (lvPPA). We sought to characterize the pattern of [¹⁸F]-THK5351 retention across all three subtypes and determine the topography of [¹⁸F]-THK5351 retention correlated with each neurolinguistic score. METHODS: We enrolled 50 participants, comprising 13 PPA patients (3 nfvPPA, 5 svPPA, and 5 lvPPA) and 37 subjects with normal cognition (NC) who underwent 3.0-tesla magnetic resonance imaging, [¹⁸F]-THK5351 positron-emission tomography scans, and detailed neuropsychological tests. The PPA patients additionally participated in extensive neurolinguistic tests. Voxel-wise and region-of-interest-based analyses were performed to analyze [¹⁸F]-THK5351 retention. RESULTS: The nfvPPA patients exhibited higher [¹⁸F]-THK5351 retention in the the left inferior frontal and precentral gyri. In svPPA patients, [¹⁸F]-THK5351 retention was elevated in the anteroinferior and lateral temporal cortices compared to the NC group (left>right). The lvPPA patients exhibited predominant [¹⁸F]-THK5351 retention in the inferior parietal, lateral temporal, and dorsolateral prefrontal cortices, and the precuneus (left>right). [¹⁸F]-THK5351 retention in the left inferior frontal area was associated with lower fluency scores. Comprehension was correlated with [¹⁸F]-THK5351 retention in the left temporal cortices. Repetition was associated with [¹⁸F]-THK5351 retention in the left inferior parietal and posterior temporal areas, while naming difficulty was correlated with retention in the left fusiform and temporal cortices. CONCLUSIONS: The pattern of [¹⁸F]-THK5351 retention was well matched with clinical and radiological findings for each PPA subtype, in agreement with the anatomical and functional location of each language domain.

The Prevalence of Rapid Eye Movement Sleep Behavior Disorder in Amyloid Positron Emission Tomography Positive Alzheimer's Disease

OBJECTIVES@#Rapid eye movement (REM) sleep behavior disorder (RBD) is well known as a prodromal symptom of neurodegenerative disease, especially α-synucleinopathy. In the previous literature, it has been reported the incidence rate of RBD in Alzheimer's disease (AD) is about 10%. This incidence rate is relatively low, if we consider that nearly half of AD patients also have Lewy body pathology. The objective of this study is to determine the incidence rate of RBD among patients with AD, confirmed by amyloid positron emission tomography (PET) image.@*METHODS@#We enrolled 57 patients with clinically probable AD patients who identified AD pathology in amyloid PET scan. RBD was evaluated with REM sleep behavior disorder questionnaire-Korean vesion (RBDQ-KR), which validated the RBD screening questionnaire as Korean version to confirm RBD. Detailed neuropsychological tests were measured using the Seoul Neuropsychological Screening Battery (SNSB).@*RESULTS@#We analyzed RBDQ-KR data collected from 57 AD patients. Dementia due to AD was 36 patients (63.2%) and mild cognitive impairment (MCI) due to AD was 21 (36.8%). AD with RBD was 14 (24.6%). Among these, AD dementia with RBD was 13 (36.1%), and MCI due to AD with RBD was 1 (4.8%). There were no significant differences in cognitive function between the patients with or without RBD, evaluated by detailed neuropsychological test.@*CONCLUSIONS@#In this study, the incidence of RBD in AD was not rare; therefore, if the patient shows symptoms of RBD, we should not rule out AD.

¹⁸F-THK5351 PET Imaging in Nonfluent-Agrammatic Variant Primary Progressive Aphasia

BACKGROUND AND PURPOSE: To analyze 18F-THK5351 positron emission tomography (PET) scans of patients with clinically diagnosed nonfluent/agrammatic variant primary progressive aphasia (navPPA). METHODS: Thirty-one participants, including those with Alzheimer's disease (AD, n=13), navPPA (n=3), and those with normal control (NC, n=15) who completed 3 Tesla magnetic resonance imaging, 18F-THK5351 PET scans, and detailed neuropsychological tests, were included. Voxel-based and region of interest (ROI)-based analyses were performed to evaluate retention of 18F-THK5351 in navPPA patients. RESULTS: In ROI-based analysis, patients with navPPA had higher levels of THK retention in the Broca's area, bilateral inferior frontal lobes, bilateral precentral gyri, and bilateral basal ganglia. Patients with navPPA showed higher levels of THK retention in bilateral frontal lobes (mainly left side) compared than NC in voxel-wise analysis. CONCLUSIONS: In our study, THK retention in navPPA patients was mainly distributed at the frontal region which was well correlated with functional-radiological distribution of navPPA. Our results suggest that tau PET imaging could be a supportive tool for diagnosis of navPPA in combination with a clinical history.

Atypical Acute Motor Axonal Neuropathy with Cerebrospinal Pleocytosis Mimicking Myelitis

No abstract available.

Pontine Infarct Presenting as Peripheral Type Unilateral Facial Palsy

Acute peripheral facial palsy usually manifests Bell's palsy of unknown cause, and rarely lacunar infarct which located in facial nucleus can mimic peripheral facial palsy. A 73 year-old man with isolated facial asymmetry diagnosed with lacunar infarction which selectively involve the facial fascicles which lie in inferolateral aspect of pons. Clinicians should take into account the possibility of central lesion and brain stem infarction, even when patients present with isolated peripheral type facial palsy.

Comparison of Outcomes after Device Closure and Medication Alone in Patients with Patent Foramen Ovale and Cryptogenic Stroke in Korean Population

PURPOSE: To compare the effectiveness of device closure and medical therapy in prevention of recurrent embolic event in the Korean population with cryptogenic stroke and patent foramen ovale (PFO). MATERIALS AND METHODS: Consecutive 164 patients (men: 126 patients, mean age: 48.1 years, closure group: 72 patients, medical group: 92 patients) were enrolled. The primary end point was a composite of death, stroke, transient ischemic attack (TIA), or peripheral embolism. RESULTS: Baseline characteristics were similar in the two groups, except age, which was higher in the medical group (45.3±9.8 vs. 50.2±6.1, p<0.0001), and risk of paradoxical embolism score, which was higher in the closure group (6.2±1.6 vs. 5.7±1.3, p=0.026). On echocardiography, large right-to-left shunt (81.9% vs. 63.0%, p=0.009) and shunt at rest/septal hypermobility (61.1% vs. 23.9%, p<0.0001) were more common in the closure group. The device was successfully implanted in 71 (98.6%) patients. The primary end point occurred in 2 patients (2 TIA, 2.8%) in the closure group and in 2 (1 death, 1 stroke, 2.2%) in the medical group. Event-free survival rate did not differ between the two groups. CONCLUSION: Compared to medical therapy, device closure of PFO in patients with cryptogenic stroke did not show difference in reduction of recurrent embolic events in the real world's setting. However, considering high risk of echocardiographic findings in the closure group, further investigation of the role of PFO closure in the Asian population is needed.

Subarachnoid Hemorrhage Showed Only on T2-Weighted Magnetic Resonance Imaging

We present the case of a 28-year-old pregnant woman with subarachnoid hemorrhage who was initially unable to undergo a CT scan and exhibited interestingly high signal intensities only on T2-weighted MRI without any signal change on fluid attenuated inversion recovery and gradient-echo imaging. These findings could be explained by a combination of factors that increase the signal intensity with elevations in the concentrations of protein and oxyhemoglobin due to massive bleeding and with the decreased fluid void signal inferred by the presence of hydrocephalus.

Diffuse Calcification Restricted on Periventricular White Matter by Primary Hypoparathyroidism

No abstract available.

Clinical and Electrophysiological Changes after Open Carpal Tunnel Release: Preliminary Study of 25 Hands / 대한임상신경생리학회지

BACKGROUND: Electrophysiological study has been known as a useful method to evaluate the therapeutic effect of operation in idiopathic carpal tunnel syndrome (CTS). The purpose of this study was to evaluate the clinical and electrophysiological changes after carpal tunnel release (CTR) compared to the preoperative results. METHODS: We analyzed the changes of nerve conduction study (NCS) before and after minimal open carpal tunnel release in 18 patients (25 hands) with CTS. Follow-up study was performed over 6 months after operation. RESULTS: Clinical improvement was seen in all cases after CTR. In contrast, electrophysiological improvement was various depending on the parameters; the mean median sensory latency and nerve conduction velocity (NCV) improved significantly (p = 0.001). The mean median motor latency also improved, but NCV and compound muscle action potential (CMAP) amplitude did not change. The extent of improvement was evident in moderate CTS, but not in severe CTS. CONCLUSIONS: In this preliminary study, all subjects who underwent CTR achieved a clinical relief along with a significant improvement of electrophysiological parameters such as median sensory latency, sensory NCV and median distal motor latency. After CTR, a number of cases with mild to moderate CTS showed a prominent improvement of clinical and electrophysiological parameters, while fewer improvements were seen in severe CTS, although it did not reach the statistical significance.

Intracranial Cystic Metastasis Mimicking Neurocysticercosis in a Pregnant Woman

Brain metastasis can form large cystic lesions, and its differentiation on the basis of imaging findings alone is difficult. A 36-year-old woman with headache visited emergency room. Two years ago, she was diagnosed as neurocysticercosis and had taken anti-parasite medications. However, in the current visit, the sizes of intracranial cystic lesions increased. Brain biopsy reported metastatic neuroendocrine tumor, and chest CT showed the primary site of the tumor. Cystic brain metastasis should be considered in cases with cystic brain lesions.

Arterial Stiffness and Functional Outcome in Acute Ischemic Stroke

OBJECTIVE: Arterial stiffness is a common change associated with aging and can be evaluated by measuring pulse wave velocity (PWV) between sites in the arterial tree, with the stiffer artery having the higher PWV. Arterial stiffness is associated with the risk of stroke in the general population and of fatal stroke in hypertensive patients. This study is to clarify whether PWV value predicts functional outcome of acute ischemic stroke. METHODS: One hundred patients were enrolled with a diagnosis of acute ischemic stroke and categorized into two groups: large-artery atherosclerosis (LAAS) or small vessel disease (SVD) subtype of Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. Each group was divided into two sub-groups based on the functional outcome of acute ischemic stroke, indicated by modified Rankin Scale (mRS) at discharge. Poor functional outcome group was defined as a mRS > or = 3 at discharge. Student's t-test or Mann-Whitney U-test were used to compare maximal brachial-ankle PWV (baPWV) values. RESULTS: Twenty-four patients whose state was inadequate to assess baPWV or mRS were excluded. There were 38 patients with good functional outcome (mRS or = 3). The baPWV values were significantly higher in patients with poor outcome (2,070.05 +/- 518.37 cm/s) compared with those with good outcome (1,838.63 +/- 436.65) (p = 0.039). In patients with SVD subtype, there was a significant difference of baPWV values between groups (2,163.18 +/- 412.71 vs. 1,789.80 +/- 421.91, p = 0.022), while there was no significant difference of baPWV among patients with LAAS subtype (2,071.76 +/- 618.42 vs. 1,878.00 +/- 365.35, p = 0.579). CONCLUSIONS: Arterial stiffness indicated by baPWV is associated with the functional outcome of acute ischemic stroke. This finding suggests that measurement of baPWV predicts functional outcome in patients with stroke especially those whose TOAST classification was confirmed as SVD subtype.

Sleep Problems Associated with Behavioral and Psychological Symptoms as Well as Cognitive Functions in Alzheimer's Disease

BACKGROUND AND PURPOSE: It has been shown that sleep problems in Alzheimer's disease (AD) are associated with cognitive impairment and behavioral problems. In fact, most of studies have founded that daytime sleepiness is significantly correlated with cognitive decline in AD. However, a few studies have also shown that nighttime sleep problems are associated with cognitive function and behavioral symptoms in AD. Accordingly, the aim of this study was to evaluate the effects of nighttime sleep on cognition and behavioral and psychological symptoms of dementia (BPSD) in AD. METHODS: The study population comprised 117 subjects: 63 AD patients and 54 age- and sex-matched non-demented elderly subjects. Detailed cognitive functions and behavioral symptoms were measured using the Seoul Neuropsychological Screening Battery (SNSB) and the Korean version of the Neuropsychiatric Inventory (NPI-K). Sleep characteristics were evaluated using the Korean version of the Pittsburgh Sleep Quality Index (PSQI-K). The correlations between PSQI-K and SNSB scores and between PSQI-K and NPI-K scores were analyzed. RESULTS: In AD patients, sleep latency was found to be negatively correlated with praxis (p=0.041), Rey-Osterrieth Complex Figure Test (RCFT) immediate recall (p=0.041), and RCFT recognition (p=0.008) after controlling for age and education, while sleep duration and sleep efficiency were positively correlated with praxis (p=0.034 and p=0.025, respectively). Although no significant correlation was found between PSQI-K and NPI-K scores, sleep disturbance and total PSQI-K scores were found to be significantly associated with apathy/indifference in AD. CONCLUSIONS: Sleep problems such as prolonged sleep duration, sleep latency, and poor sleep efficiency in AD patients were correlated with cognitive dysfunction, and especially frontal executive and visuospatial functions, and BPSD. These findings suggest that treatment of nighttime sleep problems might improve cognition and behavioral symptoms in AD patients.

Dynamic Arterial Change of Cerebral Vasoconstriction in Reversible Cerebral Vasoconstriction Syndrome

No abstract available.

Relation Between Left Atrial Enlargement and Stroke Subtypes in Acute Ischemic Stroke Patients

OBJECTIVE: Increased atrial size is frequently seen in ischemic stroke patients in clinical practice. There is controversy about whether left atrial enlargement (LAE) should be regarded as a risk factor for cerebral infarction. We investigated the association between indexed left atrial volume (LAVI) and conventional stroke risk factors as well as stroke subtypes in acute ischemic stroke patients. METHODS: One hundred eighty two acute cerebral infarction patients were included in this study. Brain magnetic resonance imaging and transthoracic echocardiography were done for all patients within 30 days of diagnosis of acute cerebral infarction. Echocardiographic LAE was identified when LAVI was more than 27 mL/m2. Stroke subtypes were classified by the Trial of Org 10171 in acute stroke treatment classification. RESULTS: There were significant differences between subjects with normal and increased LAVI in prevalence of stroke risk factors including atrial fibrillation (p = 0.001), hypertension (p = 0.000), valvular heart disease (p = 0.011) and previous stroke (p = 0.031). An increased LAVI was associated with cardioembolic subtype with an adjusted odds ratio was 6.749 (p = 0.002) compared with small vessel disease. CONCLUSION: Increased LAVI was more prevalent in those who had cardiovascular risk factors, such as atrial fibrillation, hypertension, valvular heart disease and history of previous stroke. LAE influenced most patients in all subtypes of ischemic stroke but was most prevalent in the cardioembolic stroke subtype. Increased LAVI might be a risk factor of cerebral infarction, especially in patients with cardioembolic stroke subtype.

Relation Between Left Atrial Enlargement and Stroke Subtypes in Acute Ischemic Stroke Patients

OBJECTIVE: Increased atrial size is frequently seen in ischemic stroke patients in clinical practice. There is controversy about whether left atrial enlargement (LAE) should be regarded as a risk factor for cerebral infarction. We investigated the association between indexed left atrial volume (LAVI) and conventional stroke risk factors as well as stroke subtypes in acute ischemic stroke patients. METHODS: One hundred eighty two acute cerebral infarction patients were included in this study. Brain magnetic resonance imaging and transthoracic echocardiography were done for all patients within 30 days of diagnosis of acute cerebral infarction. Echocardiographic LAE was identified when LAVI was more than 27 mL/m2. Stroke subtypes were classified by the Trial of Org 10171 in acute stroke treatment classification. RESULTS: There were significant differences between subjects with normal and increased LAVI in prevalence of stroke risk factors including atrial fibrillation (p = 0.001), hypertension (p = 0.000), valvular heart disease (p = 0.011) and previous stroke (p = 0.031). An increased LAVI was associated with cardioembolic subtype with an adjusted odds ratio was 6.749 (p = 0.002) compared with small vessel disease. CONCLUSION: Increased LAVI was more prevalent in those who had cardiovascular risk factors, such as atrial fibrillation, hypertension, valvular heart disease and history of previous stroke. LAE influenced most patients in all subtypes of ischemic stroke but was most prevalent in the cardioembolic stroke subtype. Increased LAVI might be a risk factor of cerebral infarction, especially in patients with cardioembolic stroke subtype.

Distal Subclavian Artery Occlusion Causing Multiple Cerebral Infarcts Consequence of Retrograde Flow of a Thrombus?

Intracranial embolization usually arises from the heart, a vertebrobasilar artery, a carotid artery, or the aorta, but rarely from the distal subclavian artery upstream of an embolus. We report on a patient who experienced left shoulder and forearm pain with weak blood pressure and pulse followed by concurrent onset of left hemiplegia. This case is a rare example of multiple cerebral embolic infarctions, which developed as a complication of distal subclavian artery thrombosis possibly associated with protein S deficiency.

Distal Subclavian Artery Occlusion Causing Multiple Cerebral Infarcts Consequence of Retrograde Flow of a Thrombus?

Intracranial embolization usually arises from the heart, a vertebrobasilar artery, a carotid artery, or the aorta, but rarely from the distal subclavian artery upstream of an embolus. We report on a patient who experienced left shoulder and forearm pain with weak blood pressure and pulse followed by concurrent onset of left hemiplegia. This case is a rare example of multiple cerebral embolic infarctions, which developed as a complication of distal subclavian artery thrombosis possibly associated with protein S deficiency.

Vertebrobasilar Occlusion Presenting as Sudden Isolated Bilateral Sensorineural Hearing Loss: Case Report

Isolated bilateral deafness is a rare but possible symptom of vertebrobasilar ischemia, primarily due to occlusion of the anterior inferior cerebellar arteries or their branch, the internal auditory artery. We reported on uncommon case of sudden bilateral sensorineural hearing loss without typical neurological symptoms resulting from vertebrobasilar ischemia. We performed the available examinations, including otoscopy, laboratory tests, and pure tone audiogram, however we were not able to identify the cause of bilateral sensorineural hearing loss. Brain magnetic resonance image showed the cerebellar infarction of the posterior inferior cerebellar artery territory. Brain magnetic resonance angiography showed bilateral vertebral and basilar artery occlusion. We suggest vertebrobasilar ischemia as a cause of sudden isolated deafness.

Vertebrobasilar Occlusion Presenting as Sudden Isolated Bilateral Sensorineural Hearing Loss: Case Report

Isolated bilateral deafness is a rare but possible symptom of vertebrobasilar ischemia, primarily due to occlusion of the anterior inferior cerebellar arteries or their branch, the internal auditory artery. We reported on uncommon case of sudden bilateral sensorineural hearing loss without typical neurological symptoms resulting from vertebrobasilar ischemia. We performed the available examinations, including otoscopy, laboratory tests, and pure tone audiogram, however we were not able to identify the cause of bilateral sensorineural hearing loss. Brain magnetic resonance image showed the cerebellar infarction of the posterior inferior cerebellar artery territory. Brain magnetic resonance angiography showed bilateral vertebral and basilar artery occlusion. We suggest vertebrobasilar ischemia as a cause of sudden isolated deafness.